The utility model discloses an exhaust system arrangement structure is led to to power station underground cavern construction time, it is mainly by the main building, the main room that becomes, draft tube bulkhead gate room, the down stream surge -chamber, the tailwater tunnel, highway tunnel and tail transfer the hole of ventilating to constitute, the main building, the main room that becomes, draft tube bulkhead gate room, the down stream surge -chamber, the tailwater tunnel, the highway tunnel all adopts the passageway separation of into airing exhaust, the air inlet duct combines construction branch tunnel to arrange, each big hole roof portion arranges the dedicated logical exhaust system arrangement structure who airs exhaust the adit and the shaft of airing exhaust, the beneficial effects of the utility model are that: have the good ventilation cigarette effect of loosing, a large amount of contaminated air that operation such as can guarantee will hole in the work progress, blow up, slag tap produced discharge, lead to the fact constructor health and safety to provide safeguard.